Conventional seeders commonly provide a seeder frame mounted on ground wheels for passage over a field that is to be seeded so that the frame carries a series of shanks arranged at pace positions on the frame. Generally there are three or four rows of shanks spaced forwardly along the direction of travel of the frame with the shanks being spaced also transversely of the direction of travel so that the finished array of shanks provides the required spacing of the shanks across the ground to provide a required of the spacing of the seeds when applied.
Each shank carries a furrow forming element and a seed delivery element so that the seed is deposited into the furrow behind the furrow forming element. The furrow forming element can be selected according to conditions and can comprise a narrow knife having the width in the order of two inches, a wider sweep having width in the order of six inches or still a wider shovel which can have a width up to twelve inches. In all cases the element actively lifts the soil to form a furrow through which the shank passes with the seed being deposited behind the shank into the furrow.
Many seeders are designed for single pass operation so that a packer gang is carried behind the seeder to pack the furrows with the seed deposited in the furrow. In many cases the packers are formed into separate gangs each carried on a separate frame and trailed behind the seeder frames so that the packer gangs are arranged in a row across the width of the seeder frame. The packer rollers are generally arranged so that during operation they are aligned with the shank so the each roller runs over the furrow formed by the shank with the intention of packing the soil back into the furrow.
Manufacturers and farmers have been aware that the soil which is expelled from the furrow during the forming of the furrow often does not properly return to the furrow plus tend to leave the furrow open and the seeds exposed. In addition the soil lifted from the furrow may contained clogs or lumps which interfere with the packer wheel running properly within the furrow and may act to lift the packer wheel and the gang away from the ground so the packing action is ineffective.
For example KHart Industries Ltd. of Elrose, Saskatchewan provides an element which is attached to the shank and runs behind the shank with the intention of closing the furrow. It is stated to have the benefits of:
An increase germination by helping to eliminate seed rows from drying out.
It increase even crop emergence by having an even amount of soil coverage over each see row.
It helps knock down rough soil ridges reducing equipment breakage.
This device therefore is a first attempt to solve the known problems.
In addition Concord Seeders (which are division of Case IH) disclose an arrangements which provides and additional roller behind the first and second rows of shanks which is intend to assist in the returning the soil to the furrow. This roller provides a rounded periphery and it located at a position that aligns with the next row of shanks. Plus a third row of shanks in the seeder has no associated roller. This is particular disadvantageous in that the third row of shanks provides a furrow which is therefore in formation as it is reached by the packer wheel so that there is in particular ineffective packing in respect of the third row of shanks. Thus the seeding rows are inconsistent depending on whether they are formed by the first, second or third row of shanks.
It is also known to make what are known as “disc levellers” on the shank at position behind the shank with one disc on each side of the shank so as to attempt to return the soil to the furrow prior to the packing action.
All these devices have achieved some success in resolving the difficulty but none provide a complete solution which is convenient, effective and can be mounted readily on the seeder.